Roethlisberger will start; Willis and Edwards inactive for 49ers

As expected, Niners linebacker Patrick Willis is inactive tonight due to his hamstring strain and Steelers quarterback Ben Roethlisberger will start despite his high ankle sprain.

In a bit of a surprise, however, 49ers wide receiver Braylon Edwards (knee), who was questionable, will also sit out. Edwards was also questionable last week and played in a 21-19 loss to the Cardinals, but he didn’t catch a pass and played limited snaps.

Without Edwards, San Francisco’s receivers will include Michael Crabtree, Ted Ginn, Kyle Williams and Brett Swain.

Meanwhile, Roethlisberger came out on the field on two separate occasions about two hours before kickoff to test his ankle. He began by lobbing a series of 10-yard passes and graduated to throwing passes on the move. He was noticeably hobbling as he lobbed passes while jogging. Roethlisberger limped off the field on both occasions.

Niners left tackle Joe Staley (concussion) is active and will presumably start. Cornerback Shawntae Spencer is active while Tramaine Brock is inactive. Finally, rookie guard Daniel Kilgore, a tackle in college, is active for the first time this season.